Ball-bearing pulley-block.



No. 817,074. PATENTED APR. 3, 1906. E. E. LA ROSE.

BALL BEARING PULLEY BLOCK. APPLICATION FILED JULY s. 1905.

EUGENE E. LA ROSE, UF NEW' BEDFORD, MSSACHUSETTS.

No. B 17,074

Specification of Letters Patent.

)Patented April 3, 1906.

Application filed July 3,1905. Serial Nm 268,089.

.To r/,ZZ whom t may concern:

Be it known that l, EUGENE E. LA Rose, a citizen of the United States, residing at New Bedford, county of Bristol, State oill Massachusetts, have invented certain new and use ful Improvements in Ball Bearing Pulley Blocks; and l do hereby declare the following to be a full, clear, and exact description oi' the invention, such as will enable others skilled 1n the art to which it ap pertains to maire and use the saine.

Myinvention relates to ball-bearin g pulleybloclrs, and has ior its object to provide a simple and eilicient pulley-block in which the wear is equally distributed between the sheaveerim and the hub and in which the danger ofc/rushing the balls between the rimv and the hub when sudden shocks or heavy pressures are imposed upon the block is practically ohviated.

ln pulley blocks provided with antih'ic tion hearings as heretofore constructed much difficulty has been experienced. 'trom 'the uneven wear of the bearing-surfaces on. the rim and hub and also from the crushing Vor rupturing ol'l the antiiriotion balls or roll-.`

ers due tv sudden shocks `or strains incident to the severe use to which these blocks are put, particularly' upon shipboard. y Either the unequal Wear ol the hearhig parts or the breaking oiE a single one oi" the antitriction members is sui'licie'nt to put the block out of commission, and moet blocks as heretofore constructed Were incapable of' ready adjustment or repair after they had been disabled, so that in either of the emergencies above noted the block had to be discarded. The evident cause of the uneq ual Wear on the-several parts of anantitriction pulleyblock is the unequal hearing areas 'between the saine and the inability oi the several p arts to stand the shocks and strains incident to the work they are required to do, so that the weaker .member or that which receives the greatest `wear quickly succurnbs, with the result Athat the eiliciency oi the entire device is destroyed.

Furthermore, it has been found that Where hard-steel balls have heen used as the antiiriction members the halls themselves constin tute an element of weakness, es in rolling 1n and out oi tension in a rigid raccway having no yield or resiliencyone ball oi the series is 'apt to be support/incr the entire load at the moment when 'a sudden shock. or a heavy The purpose of the present invention is tof maire the two bearing parte as nearly equal as possible as to their Wearing qualities and to provide a she'ave that issulliciently springy or resilient, so that when a sudden shook is brought upon. the bearing the sheave will give and not crush the halls. 'While this is the essential purpose of the invention, the mechanical construction ol' the pulley-block is such as to allow of ready replacing of any worn or damaged part, so that the device may be quickly repaired or adjusted without entailing the loss and delay incident to the substitution oit anew block for tho old one.

ln the accompanying drawings, Figure l is a transverse sectional elevation of a single sheave-hlock embodying the characteristic features oi my invention. Fig. 2 is i. side elevation thereof. Fig. 3 is aavertical transverse section through the hub and rim.

Referring to the drawings, o, indicates the shell or body portion ot the block preferably formed as an integral casting of brass, bronze, or similar metal having the two side plates united at top and bottom and terminating at the top in the usual eye c, which receives the pin c', to which the shackle l) is swiveled.

'lhe side plates of the shell o are provided with oppositelv-disposed openings adapted to receive a relatively large hollow bearingpin d, which is screw-threaded at one end to engage corresponding screw-threads in `the hole in the block-tace and is provided at its other end with an annular rim or flange adapted to lit snugly Within a shouldered recess formed about the edge of the hole in the opposite face oi the shell, so that the ends of said bearing-pin lie 4flush with the side walls oi the shell. The pin d has two notches cut in the shouldered end, which permit said pin to be readily removed or inserted hy means of a ilat piece of metalor epanner which engages said notches. The pin CZ serves to tie the sides of the block together in the center to prevent the side pieces spreading and also serves as a support for the sheave-bearing hub or seat. i

Surrounding the pin al and closely fitting` the saine is the hub or seat which consists of two annular telescoping sections e c, provided with upturncd AHanges lying closely along the inner walls of the shell and provided with ra'ceways ori-their outer faces 'formed in the anglebetween the side ilanfres and the annular base portions. lt willlie noted that the hub as thus formed is divided circumferentially-'and 'that' the .telescopirnT members `thereof meet to form a practicallycontinua ous peripheral surface, so that when the parts are assei'nb'led'l said hub constitutes a l is provided with raceways y', separated by an annular inwardly-projecting flange n, which serves 'to coniine a double series of antifriction-balls h between said raceways and the rcoperating raceways fi in the hub.

It will be noted that the bearing-surface between the balls and the raceways j is considerably larger than the bearing-surface between the said balls and the raceways i.

Furthermore; the outside raceways j in revolving around the inside raceways t have an effective bearing throughout practically their yentire circumference, while the inside raceways, and consequently if the raceways j and' ways t are subjected to pressure only through substantially halt of their circumference. This discre ancy is so marked that the traction area ci) the outer raceways is frequently four times as great as that of the inner racei weremade of metal of substantially the same hardness the wear on the latter would be four times as great as that on the former. In order to overcome this diflculty and to equalize the wear on the raceways, they-are made of a relative hardness in" substantial proportion to their traction areas-in other words, if the traction area of raceways'j is four times that of raceways vi the bearingsurfaces of the latter would be made substantially four times as hard Ias those of the foru mer, so that the ability of the respective raceways1 to resist Wear is rendered substantially e ua i A qAs has heretoforebeen observed, no provision lhas been made in former types of pulley-blocks to distribute pressure due to heavy shocks or strains upon the sheave to the several antifriction members sup orting the same,"which hasusually resultedpin crushing or injuring the balls.` According to the present plan this diiliculty is completely obviated, for, as will be noted, the riinf of the sheave is made relatively thin and isforined ofia metal havingsuilicient ductility.andfresiliency to permit it to be temporarily' deformed under eavy strains or shocks and toltspring around ftheballs and distribute thtr pressure to each of them'should one ball bein position to take the load at the moment oigreatest strain. After the strain has been relieved, the resiliency of the rim f causes it to immediately assume its proper annular iorin Vand to run smoothly on the balls.

ln order to exclude dust and dirt from the working parts vof the sheave and to retain a proper lubricating material, such as oil7 in' the bearings, annular washers g of ielt are disposed in suitable grooves on the inside faces of the hub to bear against the lateral edges of the rimf, as clearly indicated in Figs. l and 3. Y

lt will be noted in addition to the advan- 'tageous features liereinbefore set forth that my improved pulley-block involves a construction that is readily assembled or dismembered and that it may be easily adjusted and repaired without loss oi time.

In assembling the various parts of the block the two sections of the hub are brought into proximity to the rim f, the balls inserted in the raceways, and the two sections of the hub forced together at the telescoping joint, after which the sheave with its hub is insert* ed between the side walls of the shell c and the bearing-pin CZ slid through the openings in the side walls and the central opening in the hub and screwed home. ln order to replace any injured or worn part, the reverse operation is carried out7 and the injured part-as for example, one or more of the ballsI a hub-section, or the rimis removed and a duplicate part substituted therefor, after which the several parts are reassembled;

vWhile the invention has been described with particular reference to a single sheaveblock7 it will be obvious that it is equally Well adapted to multiple sheave-blocks, and whileparticular attention has been given to the Vdetails of construction in the description it is to be noted that the invention is not to be limited to such details, but is to be accorded such scope as the claims indicate.

Having thus. described my invention, what l claim, and desire to secure by Letters Patent, isl j l. A sheave, comprisinff an annular rim, a hub, and antifriction-balls between the rim and the hub the bearing-faces' of the rim and hub having a relative hardness in substann tial inverse proportion to their respective contact-surfaces with thev balls, whereby wear on the rim and hub is equalized.

2. A sheave, comprising an annular rim, a hub, each having raceways formed therein7 and antifriction-balls in said raceways, the respectiveraceways having faces of a hardness in substantial inverse proportion to the contact-surfaces of each with the balls, whereby wear on the rim and hub is equalized.

3. A sheave, comprising an annular resilient rim capable of temporary deformation, a

hub, andvv antii'ricticn-balls between the rim (ler slwvks m' strains ru (lisirihull llw prvs l the Wozu' 0x1 thv rim :unl hul) is oqlmlizvnl nmlthe rlm wlll )wld mulvr shocks :lml srnlin: l0 :Word crushing,I thv: hulls.

6. A pulley-block, comprising :l shell m* `body partumI :L trmlsvvrso lwnrrngmm, :1.`

hul) having :L irffuml'vronlinl rmfvwny von swirl pin, :1.11 :mnuhrr resilivnlv rim hm'lhg :1` racewny on .its intorior 121:00, :md :Lnllfrirtiulb balls nsnid l'zruinvnfys, .mid rim bring' :ulupled to yield umlor` Shocks :md strains to rulieve the balls from rupturng-i)rossurv.

7. A pL1ll0y-,l)l0(-,k,comprising' :L slwll 0r body portion, :L hollow'hearing-pin rouwvably supported in the sides nl will shall, :l

Ihub formed of tvlescoping soc/Lions mounted huh, :md gungrll-wnslu-rs lmlzwvnu the hub 

